My '87 260E has a growling sound that seems to be coming from the transmission. From the drivers seat the sound is in front of me in the center. From the side of the car it also seems to be coming from the transmission and not the engine judging by location. The sound increases directly with the engine rpm. Makes no difference if the car is in gear or not.
Any ideas on what could be causing this?
1987 260E, 79K miles